libCVD is a very portable and high performance C++
library for computer
vision, image, and video processing. The emphasis
is on providing simple
and efficient image and video handling and high
quality implementations
of common low-level image processing function. The
library is designed
in a loosely-coupled manner, so that parts can be
used easily in
isolation if the whole library is not required.
The video grabbing
module provides a simple, uniform interface for
videos from a variety
of sources (live and recorded) and allows easy
access to the raw pixel
data. Likewise, the image loading/saving module
provides simple, uniform
interfaces for loading and saving images from
bitmaps to 64 bit per
channel RGBA images. The image processing routines
can be applied easily
to images and video, and accelerated versions
exist for platforms
supporting SSE.

Tuwo is a C++ library for solving high-level computer vision tasks such as image classification and object recognition. Computer vision is a subfield of computer science and deals with systems that can make sense of image information. Building systems suited for high-level computer vision tasks such as object recognition and image classification requires the use of robust image statistics in the form of image features and machine learning algorithms to separate discriminative information from noise. This C++ library provides code to extract image features and learn decision functions from training data. It is suitable for high-level computer vision tasks.

Into is a cross-platform machine intelligence application framework written in C++. Into provides a different, fast way to build high-performance applications for image analysis, machine vision, pattern recognition, and artificial intelligence. It features a layered API and more than 20 fully interoperable plug-in modules for accessing image and data sources, powerful feature extractors, classifiers, neural networks, and much more. It also provides Ydin, an innovative execution engine that makes it easy to create dynamic programs that automatically run in parallel, enabling you to create more with less hassle, less code, and less time. Into uses Qt to let you create beautiful user interfaces for your applications with ease.

Mahotas is an image processing library for Python. It includes a couple of algorithms implemented in C++ for speed while operating in numpy arrays. The main algorithms are watershed and Otsu thresholding.

Accord.NET provides statistical analysis, machine learning, image processing, and computer vision methods for .NET applications. The Accord.NET Framework extends the popular AForge.NET with new features, adding to a more complete environment for scientific computing in .NET.

Fluere is a graphical software package for particle image velocimetry (PIV). Fluere is highly optimized for parallel processing and runs on multiple platforms. The goal of the project is to provide researchers and educators with high-quality velocimetry software that incorporates the latest advancements in PIV processing, while having complete knowledge of the algorithms used.

Qt-based library with functionality to create highly efficient and fully graphical applications, oriented to computer vision, image processing, and scientific computation. The library features an homogeneous and well documented object-oriented API, with wrapping methods for high performance functionality from libraries such as OpenCV, GSL, CGAL, IPP, BLAS, LAPACK, or Octave library.

imread is a simple library which reads and saves images from disk to and from numpy arrays. Its goal is to perform this task simply, so that it can become very stable, leaving more complex image processing for other packages.